[tscs37]

Even a perfect kernel will have to crash.

Something like Rowhammer can turn perfectly written code into malicioous gadgets for an attacker. Until ECC or preventative measures becomes widespread in consumer hardware, this attack will remain viable.

Additionally, cosmic rays may at any time write arbitrary data into memory. In these situations it is perfectly reasonable to crash the machine if essential datastructures were affected.

Or suppose you just received a MACHINE CHECK exception, the type of interrupt which essentially just tells the OS that the machine is no longer capable of operating in it's current state.

This isn't all about an attacker gaining privilege, the mere act of crashing the kernel in a hostile or other event (cosmic rays, voltage fluctuation) which leads to corruption or compromise of the continued operation of the machine is perfectly acceptable and normal.